top | item 21660003

(no title)

chaosfox | 6 years ago

I don't think I understand the problem.. to do this search you need to have the target number, and if you already have the target number no search is required.. what am I missing ?

discuss

order

tyoma|6 years ago

So the goal wasn’t to find a new and more expensive method for figuring out an answer when you can examine the oracle. The idea was to show that an “impossible” problem isn’t really that impossible given some thought about the algorithm and the computing power easily accessible today.

The impetus for doing this was though a real discussion when we were debating whether to do an analysis to identify some constants, or just to brute force comparisons. At what point was the analysis faster? One thing led to another and next thing I know I was learning CUDA...

saagarjha|6 years ago

It’s a thought experiment to figure out how long it takes to brute force a 64-bit space. In reality you won’t have the number you’re searching for.

bonoboTP|6 years ago

But in reality you'd need to do some complicated operations on each 64-bit item, right? When e.g. cracking a password or so.

I also don't understand what type of real-world application is being simulated here. I do understand that it is a simplified example, but of what?

The takeaway is that it is feasible to perform a single comparison operation for each 64-bit bitstring. But we don't just do a single operation per item in the real world.